The present invention relates to military training systems and methods, and more particularly, to a system and method particularly adapted for simulating tank fire in simulated war games.
Combustion powered artillery has long been classified according to the path or trajectory of its projectile. A motor lobs its shell in a high parabolic path. The shell fired from a gun, such as a tank gun, has a direct somewhat level and slightly downwardly curved path. The shell from a howitzer makes a useful compromise, traveling over an arcuate path of considerable distance requiring less propulsive explosive and a lighter barrel than that of a gun.
The United States Military has developed and extensively used the Multiple Integrated Laser Engagement System (MILES) for turning ground forces in military operations. Rifles are fitted with low power lasers and simulated kills are made by hitting a soldier wearing a vest carrying optical detectors. In more elaborate inplementations, indirect fire from mortars and howitzers can be simulated, as well as mine fields, in some cases by using player units equipped with Global Positioning System (GPS) locators. Pyrotechnics and sound have been added to provide enhanced realism.
Tanks are still a very important component of ground assault operations. Any laser based system for simulating gun fire from a tank must take into account the fact that a real projectile, such as a one hundred and twenty millimeter shell, follows a curved trajectory and takes a substantial amount of time to move from the tank to the target or target area. In contrast, a laser beam moves in a straight line at the speed of light. Numerous gunnery training systems have been developed such as those disclosed in U.S. Pat. Nos. 3,588,108; 3,609,883; and 3,832,791. U.S. Pat. No. 4,218,834 of Robertson entitled, SCORING OF SIMULATED WEAPONS FIRE WITH SWEEPING FAN-SHAPED BEAMS discloses a gunnery training system designed to more accurately simulate tank fire in complex tactical situations than the systems of the three U.S. patents mentioned earlier. Flat-wise angularly sweeping beams of laser radiation are emitted at or about the instant of simulated canon fire. These same beams are also used to measure the position of a target retro-reflector in range in terms of azimuth and elevation. During this same time period a calculation is made of the instantaneous position in terms of range, azimuth and elevation of a simulated projectile. The relationship is calculated between the simulated projectile and each beam in its angular position at interception by the retro-reflector. At the scoring instant when the weapon-to-reflector distance equals the weapon-to-projectile distance, or when the projectile is at a predetermined elevation relative to the reflector, scoring is based on the relationship of the projectile to the angular beam position at the aforementioned instant. Scoring results are displayed in the tank and/or transmitted to the target in beam modulation for evaluation of hit effect at the target.
While the system and method of the aforementioned Robertson patent has been commercialized with some degree of success, it would be desirable to provide a more precise gunnery training system that takes advantage of GPS locators and has improved capabilities and flexibilities to further enhance the realism of the tank gunnery training exercise in complex tactical situations.
In accordance with the present invention a gunnery simulation system includes a gun with an emitter in its barrel that emits a beam of optical radiation at a first location upon a trigger pull. The beam is directed toward a target at a second location based upon a shooter""s conventional ranging and tracking. The target is scanned with the beam of radiation to measure a target azimuth and a target elevation with respect to a boresight of the gun. A time of the trigger pull is transmitted to the second location. Optical receivers at the second location detect the beam of optical radiation and a system control unit determines the target azimuth and target elevation. The system control unit also determines a range to the target by comparing a set of GPS coordinates of the gun and the target. Based on the target aznimuth, the target elevation, the range to the target and the time of the trigger pull the system control unit computes an impact point relative to the target of a simulated ballistic shell fired from the gun at the time of the trigger pull.